Priority is claimed on Japanese Patent Application No. 2005-378023, filed Dec. 28, 2005, the contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a door construction for a tailgate (a back door) or the like of a vehicle, and a manufacturing method for a vehicular door.
2. Description of the Related Art
An ordinary door for a vehicle is constructed by: unitarily joining an inner panel on a cabin interior side and an outer panel on a cabin exterior side; and attaching an interior decoration cover facing the cabin interior side, thereto. The outer panel and the inner panel are joined with each other by performing a hemming onto peripheries of these panels (for example, refer to Japanese Unexamined Patent Application, First Publication No. H07-80559).
In more detail, as shown in FIG. 7, while in a state in which hemming flanges 53 to be bent onto an inner panel 52 side are formed on a periphery of an outer panel 51 and the inner panel 52 overlaps the inside of the outer panel 51, the hemming flanges 53 are bent so as to overlap the cabin interior side of the inner panel 52. Moreover, FIG. 7 shows a flap-type tailgate (a back door) of a vehicle. The reference symbol 54 in FIG. 7 denotes a hinge which attaches the tailgate to a vehicle such that the tailgate is rotatable in the vertical direction.
On the other hand, as shown in FIG. 8, there is a door for a vehicle which is formed in a curved-shape such that the cabin interior side thereof forms a concaved-shape. In the case in which the above-mentioned construction is applied to this type of door, the hemming flanges 53, which are preliminarily bent before overlapping the inner panel 52 onto the outer panel 51, form an undercut-shape with respect to a main body of the outer panel 51, as shown in FIG. 9. That is, the preliminary bending angles of the hemming flanges 53 are a substantially right angles (90°to 100°) so as to prevent dislocation while setting the outer panel 51 onto the inner panel 52, and the curved direction of the outer panel 51 and the bending direction of the hemming flange 53 are the same; therefore, the hemming flanges 53 form the undercut-shape with respect to a main body of the outer panel 51.
In addition, in the case in which the above-mentioned conventional construction is employed, since the hemming flanges 53 form the undercut-shape at the preliminary bend with respect to the main body of the outer panel 51, as shown in FIG. 9, a large difference occurs between the pressing direction of an entire of the outer panel 51 and the bending direction of the hemming flanges 53. Therefore, a metal mold 55 for bending the hemming flanges 53 has to be driven independently with respect to the above-mentioned pressing direction using cams or the like; and furthermore, the a metal mold 56 for receiving the bent outer panel 51 has to be removed from the undercut section by making slide it in the direction substantially perpendicular to the pressing direction after forming the outer panel 51. Accordingly, a concern is that press-working of the outer panel 51 is complex, and thereby introduces an increase in facility cost.
Furthermore, in the case in which the above-mentioned conventional door construction is employed, since the hemming flanges 53 at the preliminary bend form the undercut-shape with respect to the main body of the outer panel 51, an opening width between the hemming flanges 53 of the outer panel 51 becomes smaller than the total width of the inner panel 52, as shown by “(A)”in FIG. 8. Therefore, in order to set the inner panel 52 onto the outer panel 51, one end of the inner panel 52 has to be inserted into the inside of the hemming flange 53 while inclining the inner panel 52 as indicated by “(B)”in FIG. 8; and thereafter, another end of the inner panel 52 has to be pushed into the inside of the hemming flange 53 while rotating the outer panel 51 as indicated by a white arrow in FIG. 8. Therefore, operations for setting the inner panel 52 to the outer panel 52 before the hemming, becomes complex. Thus, it has been desired to make this setting operation simpler and thereby improve the working performance.
The present invention was made in view of the above circumstances, and has an object of providing a door construction for a vehicle, and a manufacturing method for a vehicular door which enables improving the production performance by making it easier to preliminarily bend a hemming flange before hemming and to perform setting between an inner panel and an outer panel after the preliminary bending.